This invention relates to a start-control method and circuit for an optical disc play-back system and particularly useful for battery-driven optical disc play-back systems.
Generally, compact optical audiodisc players, one kind of optical disc play-back system, exhibits reproduction properties considerably superior to those of conventional, phonographic audiodisc players. These optical audiodisc players include complicated servomechanisms suitable for accurate bit-wise retrieval of information stored on an optical disc and consumes a great deal of electrical power. This high rate of consumption of electrical power is chiefly due to the fact that the search current used in focus search operations and various other currents are used in addition to the starting current for the disc drive motor, resulting in the need for a high-power electrical supply.
Accordingly, a battery-driven optical disc player generally requires a battery capable of supplying the significant electrical power needed to start the motors, which in turn considerably reduces the service life of the battery. On the other hand, the use of a battery with a large capacity increases the weight of the battery, thus making it difficult to achieve a compact and light optical disc player.